Bus bar and bushing connection



Oct. 30, 1934. c. w. ROBERTS 1,978,649

BUS BAR AND BUSHING CONNECTION Filed Feb. 11, 1930 Jmemtoz (ya /es .1?069 Patented Oct. 30, 1934 UNITED STATES BUS BAR AND BUSHING CONNECTIONCharles W. Roberts, East Milton, Mass usignor to Locke InsulatorCorporation, Baltimore, Md., a corporation of Maryland ApplicationFebruary it, 1930, Serial No. 427,567

8 Claims.

The invention relates to connections between bus bars and bushings.

It is well known that it is desirable to make an electrical contactbetween a bus bar passing through a bushing and a conducting surface onthe inside of the bushing inorder that corona formation and subsequentsplitting of the bushing will be avoided. The fundamental principle ofconnecting an energized bus bar with the side wall of a bushing isneither new nor unique and the proposition need therefore not bediscussed in minute detail. It is also known that it is desirable-tosupport a bus bar mechanically within and with respect to the bushingthrough which it passes so that it will be adequately supported andproperly centered. I

It is with the above facts in view that I have devised the presentinventionwhich has for its general object the provision of a novelinsert adapted to be placed within a wall or other similar bushing inelectrical and physical contact therewith and also in mechanical andelectrical engagement with the bus bar or bars.

An important object of the invention is to provide an insert of thischaracter which will closely frictionally engage the inner surface ofthe bushing, regardless of slight variations in the diameter thereof andwhich will also have proper and perfect contact with the bus bar or barseven though they may vary in their dimensions.

Another object of the invention is to provide a device of this characterwhich when inserted will remain in place without any necessity for theemployment of auxiliary or extraneous fastening means, friction beingthe sole force relied upon. An additional object is to provide a deviceof this character which willbe simple and inexpensive to make, easy toinstall, positive in action, efficient and durable in service, and ageneral im- 40 provement in the art.

-To the attainment of the foregoing and other objects and advantages,the invention preferably consists in the details of construction and thearrangement and combination of parts to be hereinafter more fullydescribed and claimed, and illustrated in the accompanying drawing inwhich:

Figure 1 is a longitudinal section through a bushing equipped with mydevice showing one form thereof,

Figure 2 is an end elevation with the bus bar in section,

Figure 3 is a view similar to Figure 2 but showing two bus bars, and

Figure 4 is a side elevation thereof with parts broken away and insection.

Referring more particularly to the drawing, the I numeral 10 designatesa wall or other similar bushing which is generally provided with acorrugated outer surface 11 and a smooth cylindrical bore 12 which inthe carrying out of the present invention is intended to be providedwith a metallic or other conducting coating. The numeral 13 designatesthe bus bar which extends through the bushing and which is to besupported therein. To accomplish the desired result I preferably makeuse of a disk-like body member 14 which in the present instance isrepresented as having a shape similar to that of a grooved pulley, or inother words having a peripheral flange 15 which is concaved for theretention of a helical spring 16 which is arranged in the form of a ringand which frictionally engages within the grooved periphery. The hubportion 17 of the disk-like body is shown as formed with a socket 18communicating with aslot 19 through which the bus bar 13 passes, andlocated within this socket is a coil spring 20 bearing against andmaking electrical contact with the bus bar. Any means may be providedfor holding the spring in place and in the present instance I havedisclosed for thls purpose a metal plate 21 held as by screws 22. .Asthe body 14 is of conducting material it is quite apparent that therewill be an electrical connection between the bus bar and the conductingsurface on the inside of the bushing. The spring 20 insures contactbetween the bus bar and the body and the ring shaped helical spring 16insures firm mechanical and electrical connection with the wall of thebore. Clearly the bus bar is mechanically supported in centered positionwithin the bushing. In cases where it has been proposed to use a bus barrectangular in cross section difliculty has been experienced in mountingit satisfactorily within the bushing but by my device this becomes anextraordinarily simple matter.

In Figures 3 and 4 I have illustrated a slight modification in which thebody 14 is formed with two slots 19*- for the reception of bus bars 13',there being two sockets l8 containing springs 20" retained in place bymetal plates 21 fastened as by screws 22.

Regardless of the number of slots and bus bars it is apparent that theoperation is identically the same. Attention is called to the fact thatthe springs contacting with the bus bar or bars will insure propercontact even though there may be variations in the dimensions of thebars. Fur thermore as the ring shaped helical spring around theperiphery of the body is compressible there is bound to be good contactwith the bore of the bushing even though there may be considerablevariation in the diameter thereof, of course within certain limits.

5 From the foregoing description and a study of the drawing it will beapparent that I have thus provided a very simply constructed,inexpensive and easily applied device for the purpose specifled whichwill be highly efflcient in every respect. It is'believed that theconstruction, operation and advantages will be readily apparent to oneskilled in the art without further explanation.

While I have shown and described the preferred embodiment of theinvention, it should be understood that the disclosure is merely anexemplification of the principles involved as the right is reserved tomake all such changes in the details of construction as will widen thefield oi utility and increase the adaptability oi the device providedsuch changes constitute no departure from the spirit of the invention orthe scope of the claims hereunto appended.

Having thus described the invention, I claim: 1. Means for mounting abus bar within an insulating bushing, comprising a body memberadapted'to conform to the bore of the bushing and apertured for thepassage of the bus bar, a coil spring surrounding the periphery of thebody and adapted to bear compressingly against the wall of the bore ofthe bushing, and spring means carried by the body and adapted to bearagainst the bus bar.

2. Means for mounting a bus bar within a bushing insulator having aconducting inner surface, comprising a body member of conductingmaterial apertured for the passage of the bus bar, spring means carriedby the body and entering the aperture and adapted to compressinglyengage the bus bar, and spring means carried by the body at itsperiphery and adapted to cornpressingly engage the wall of the bore ofthe bushingl 3. In combination with a bushing insulator and a bus barextending therethrough, a connection therebetween comprising conductingmeans emtor.

5. Means for holdinga bus bar in a bushing insulator through which itextends, comprising t a conducting member adapted to be located adjacentthe bus bar and formed with a pocket, spring means confined within saidpocket and adapted to engage against the bus bar, and other spring meansconfined to said member and adapted to engage the wall of the bore 01the insulator.

6. Means for mounting a pair of spaced bus bars within a bushing throughwhich they extend, comprising a metallic member of disk form providedwith spaced slots adapted to receive the respective bus bars, springelements contained within said disk at the outer sides of the slotstherein and adapted to bear against the bus bars,

and a coil spring seated about the periphery of the disk and adapted tobear against the wall of the bore of the bushing.

7. Means for mounting a bus bar within an insulating bushing, comprisinga body member apertured for the passage of the bus bar, a spring mountedon the body and adapted to bear compressingly against the wall of thebore of the bushing, and other spring means carried by the body andadapted to bear against the bus bar.

8. Means for mounting a bus .bar within a bushing insulator, comprisinga body member apertured for the passage of the bus bar, spring meanscarried by the body and adapted to compressingly engage the bus bar, andother spring means carried by the body at its periphery and adapted tocompressingly engage the wall of the 20

